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Over the same period, the rate of such births in every other age group fell, apart from in the under-20s, where IVF is not a major factor.

The increase in the over-45s' rate comes at a time when the Human Fertilisation and Embryology Authority (HFEA) and the National Institute for Health and Care Excellence (NICE), have been intensifying efforts to reduce the numbers of multiple births.

Earlier this year, Nice introduced new guidelines on how many embryos should be used. The numbers varied according to different factors, but clinics were encouraged to reduce them.

The HFEA, which regulates clinics, has been gradually reducing the target it sets for the number of multiple births. Last year, it said that no more than 10 per cent of IVF births should be twins or triplets.

Last year, the figure was around 16 per cent. A spokesman said: "We are getting the multiple birth rate down overall. Things are moving in the right direction."

Overall, the ONS report shows that 11,228 women had multiple births last year, with the rate down from 16.1 per 1,000 pregnancies in 2011, to 15.9.

This compares with a rate of just 9.6 in 1976.

The largest increase was recorded between 1990 and 1995 - as IVF treatment became more widespread and effective - when the rate rose from 11.6 to 14.1, a rise of 22 per cent.